Stabilizing device



Feb. 28, 1933. I W ICHATER 1,399,079

STABILIZING DEVICE Filed March 8, 1952 4 Sheets-Sheet l Feb. 28, 1933. w. CHATER 1,899,079

' Q STABILIZING DEVICE F'iled March 8, 1932 4 Sheets-Sheet 2 Q 9' r K I 79 w 29 ,2; '29 av m M 103 I 34 [nae/rial.-

W. CHATE'R I STABILI Feb. 28, 1933;

ZING DEVI GE Fi led March 8, 1952 4 Sheets-Sheet 3 m n w I m'llz'am Cbafen Feb. 28, 1933. w. CHATER 1,899,079

STABILIZING DEVICE Filed March 8, 1932 4 Sheets-Sheet 4 Patented Feb. 28, 1933 UMTED STATES WILLIAM cnn'rnn, or DENVER, coLon-Ano' YSTABILIZINGY nnvrcn I Application filed March 8,

An object of this invention is to provide an improved stabilizing device. l

v A further object of the invention is to provide an improved stabilizing device suscepti- 5 ble of installation in air and water craft and operable to preserve balance of such craft in either or both lateral and longitudinal planes.

A further object of the invention is to provide an improved stabilizing device which is 0 fully automatic in operation.

A further object of the invention is to pro vide an improved stabilizing device which is non gyroscopic and in which all of the constituent elements are normally at rest.

A further object of the invention is to provide an improved, gravity-operable control unit in a stabilizing device.

A further object of the invention is to provide an improved apparatus where through displacement of anormally balanced control unit may function to alter the plane of its supporting craft.

. A further object of the invention is to provide' an improved stabilizing device which is light in weight, positive'in operation, simple and inexpensive of installation, and susceptible, in aircraft, of connection with the normal controls of such craft'for stabilizing effect through the normal control surfaces of the craft.

My invention consists in the construction, arrangement and combination of elements hereinafter set out, pointed out in my claims and illustrated by the accompanying drawings,-in which- Figure '1 is a conventionalized view ofa portion of an aircraft wherein the improved stabilizing device is shown mounted andconnected for'practical use,portions of the aircraft being omitted and broken away for greater clarity and to conserve space. F igure 2 is a diagrammatic view showing one method of connecting the stabilizing device with the normal controls of an aircraft. Figure 3 is a detail view, on an enlarged scale, showing a preferredmethod of yieldingly interconnecting operating cables of the stabilizing device and control cables of an aircraft. Figure 4 is a side elevation of the gravity-operable control unit assembly em- 1932. ,Serial No. 537,569.

ployed in the improvement. Figure 5 is a plan view of the showing of Fig.4. Figurefi isan end elevation of the showing of Figure 4. Figure-7 is a vertical section taken on the transverse-median line of the balancedv unit alone, other elements of the control assembly being omitted. Figure 8 is a side elevation of the operating assembly employed in the improvement; Figure 9 isa plan view of the showing of-Figure 8. Figure 10 is a vertical section taken on the indicated line1010 of Figure 8. Figure llis a diagrammatic view showing one method of applying the invention to Watercraft to minimize rolling thereof. Figure'12 is a plan view, partlyfin section, of the arrangement shown in Figure- 11. Figure 13 is an isometric, detail view,

on an enlarged scale,-of the keel rudders em' ployed in the arrangement shown in Figures 11 and 12. Figure 14 is a conventionalized diagram of the electrical devices and wiring employed in the improvement.

The invention comprises two distinct'assemblies, one, the control unit assembly, being mounted in any convenient location on the supporting craft and arranged with its base in the normal horizontal plane of the craft and its axis of oscillation parallel with that craft axisabout which stabilization is to be eifected, the other, an operating assembly, being operatively connected with certain control surfaces carried by the craft and hence so locatedand installed on the craftas-to facilitate such connection, the opera-tiveinterrelation between the two assemblies being bad through electrical connections readily adaptable to. a wide variety of specificj-installations. I A i In the construction of the control unit as sembly, a balanced, tiltable control unit is indicated generally bythe numeral 15,-vvhich unit is formed of a plurality of'elongatedcells 16 arranged in nested relation and securely clamped together in any suitable man.- ner, similar plates 17 and 18 bearing against the top and bottom, respectively, of the cell assembly and. rigidly interconnected by meansof bolts or rivets 19 being illustrated as one convenient and satisfactory clamping means. The cells 16 are identical, one with another, and maybe employed in such numher as may be desirable for a specific installa- 7 tion, twenty-four such cells being illustrated in this instance. Each of the cells 16 is shown as I a relatively long, hollow box 7 or tube formed of any suitable material in any con- V,'the free ends of said cells being elevated equal amounts above their centers and the v dihedral angle thus formed lying in the vertical :plane of the assembly. While the cells are shown as straight on each side of their centers, it may of course be desirable in some instances to have them curved, the principle of operation being the same in either case.

3 overcome which condition means are. pro- V lation on and relative to saidbase.

. Lugs21 depend in spaced relation from the lower side of the assembl 15 in alinement beneath the apex of the dihedral angle thereof, which lugs support anti-friction devices 22 wherethrough is received a fixed shaft or axle 23 suitably supported on'and in spaced, parallel relation above a base 24, thus mounting the assembly 15 for limited oscilits mounting and'consequent high center of gravity,-the assembly 15 is very sensitive and highly unstable and may'not readily assume its balanced position shown in Figure'4, to

vided operable to yieldingly support said assembly in the balanced position shownj'which 'means further act to resist minor oscillations of said assembly, which means are hereinafter described. Adjacent one end of the shaft 23 a pedestal 25 is fixed to and rises from the base 24, the upper end of which 7 pedestal is so formed as'to provide. a pair of downwardly-opening yokes 26 in' spaced, -parallel relation on opposite sides of the transverse median line of the assembly, across each of which yokesis rotatably mounted a short shaft 27 so positioned as to lie in parallel relation with the shaft 23. From the end of each shaft 27 most nearly adjacent the assembly 15, an arm 28 extends outwardly 7 toward the free end of said assembly. the free through and hooked beneath a side margin of end of eacharm 28 being pivotally linked to apull rod 29 looselyiengaging at one end the clamp plate 18, so that, when one end of V theassembly 15 is depressed. the pull-rod on that side of said assembly is moved downwardly and acts to rotate its respective shaft 27,1while the pull-rod on the other side'of the assemblyslides freely through its por tion of the plate 18 as said plate rises relative thereto. In substantial alinement longitudinally of the base 24 with the pedestal 25 Due to and equally spaced on opposite sides thereof, similar pedestals 30' rise from said base ad jacent the'free ends of the assembly 15, each of which latter pedestals supportsa bellcrank 31 pivotally mounted at its angle for actuation through a vertical arc and so arranged as to be normally positioned with one of itslegs extending vertically upward and its other leg substantially horizontal and ex- .tending in the. direction of the free end of the assembly 15, an adjustable stop 32"carried by an extension of the pedestal 30 being positioned above the horizontal leg of said bell-crank and arranged limit upward arcuate travel thereof. Ami arm 33 depends from each of the shafts 27 at substantially right angles with its adjacent arm 28 to lie inapproximatelythe'same vertical. plane with its adjacent vertical leg of the bell- 'crank31, and a retractile coil spring 34 op:

eratively interconnects each arm 38 and the vertical leg of its adjacent hell-crank 81, adjusting means, such-as turnbuckles, being provided for the springs 34 'which,'in combi-, nation with a plurality of spring-attaching points in'the arms 33 and vertical'legs of the bell-cranks 81, permit variation and adjustment of the tension and. leverage applied through said springs 34." Rollers 35 are mounted for free rotation on stub shafts extending horizontally from the clamp plate 18 adjacent the free ends of the assembly 15, said rollers 35' being thus positioned adjacent and for rolling contact with the horizontal legs of the bell-cranks 31, the outer ends of which horizontal legs are curved out- I wardly and downwardly to provide arcuate surfaces adapted to be engaged by said rollers and operative to retard the speed of oscillation of the assembly 15. It is obvious that the arrangement above described serves to steady the assemblv'15 in its balanced. position, the tension of the springs 34' having to be overcome before said assembly'may tilt appreciably, said springs and connections acting further to return the assembly promptly to its balanced position when the base 24 approaches thehorizontal. To pro.- vide for positive. tilting-action of the'-*as-, sembly 15 as the base 24 is moved from its normal horizontalposition, the cells 16 are charged with liquid through the openings provided for that purpose, each of the cells receiving an equal amount of theliquidand' only so much as 'may be received without V ouite filling the mid-section of each'cell when I the assembly is in'balanced'position. I The liquid employed may vary in kind and quantity in specific installations, but should be characterized, generally, by ilow expansive and. contractive coefiicients, a low freezing point and freedom from corrosive effects. It

is readily apparent that with the .cells charged asabove set forth, any'longitudinah tilting ofthe base 24 causes the liquid within the cells 16 to move toward the low end of said base and thus unbalance the assembly 15, overcoming the tension of :the springs 34 and depressing that end of said assemblyadiacentsthe low end of the base, in which position the assembly is held by weight of the liquid until such time as the base again approaches the horizontal and the liquid is permitted to return to the center of the assembly, whereupon the springs and related connections return said assembly toits balanced position with a minimum of oscillation. Three electrical switches are positioned on the base 24 for operation and control by theass-embly 15,two of said switches, designated by the numerals 36 and 37 being positioned adjacent the free ends of said assembly and the third switch, 38, being located adjacent the pedestal 25 beneath and between the yokes 26 thereof. The switches 36 and 37 are identical in form, style and operation and may be constructed in any suitable manner to accomplish the results desired, those shown in the drawings comprising each a base portion 39 secured to the base 24 and carrying a pair of spaced contacts, and an upper portion 40 hinged at one end to said base portion for actuation through a vertical are relative thereto and carrying a pair of spaced contacts adapted at times to register with and engage the contacts of the corresponding base portion. The upper portions 40 of the switches 36 and 37 are operativelv connected with the adjacent ends of the assembly 15, fins 41 rising from said portions 40 and formed with longitudinal slots adapted to engage about and slide on pins 42 fixed to and projecting laterally from said assembly 15 being shown as one suitable means of effecting the connection desired, the relation of the connected elements being such that both switches 36 and 37 are held in open circuit position when the assembly 15 is'in its normal balanced position and either of said switches being movable to closed circuit position through tilting action of said assembly. the switch adjacent the depressed end of said assembly being. naturally. the one to be so closed. The switch 38 likewise com rises a base portion 43 fixed to the base 24 and carrying a pair of spaced contacts and an upper portion v44 hinged to said portion 43 for actuation through a vertical arc and provided with spaced contacts adapted to engage at times with the contacts of the fixed portion. It is desired that the switch 38 be held in closed circuit position whenthe assembly 15 is in its balanced position and moved to open circuit position when said assembly tilts in either direction, to which end links 45 are hinged at their lower ends to the switchportion 44 and rise therefrom to pivotal connection at their'upper ends with arms 46 fixed to and extending inwardly fromithe shafts 27, so that when either of the shafts 27 is rotated by tilting action of the assembly 15, the free end ofthe arm4\ carriedby said shaft is moved upwardly through a vertical arc and acts through its linizl45 to' lift the switch portion 44 and disengage the contacts of the switch 38, a stem' 47 pivoted at its lower end to the switch portion 44 rising therefrom through a guide aperture in the upper portion of the pedestal 25 andsupporting an expansive coil spring 48-bearing between the upper portion of said pedestal and an annular flange carried by said stem and operable to urge the switch portion 44 into contact engagement with the switch, portion 43; Thus, when the assembly 15 is in its balanced position the switch 38 is inclosed circuit position and the switches 36 and 37 both in open circuit position, tilting of the assembly 15 serving to open the switch '38 and close the switch 36 or 37 adjacent the de pressed end of said assembly, which closing of a switch 36 or 37 serves to limittilting action of the assembly. v

The operating assembly wherethrough the tilting action of the assembly 15' is made effective comprises a suitable base 49 whereon two identical electric motors '50 and 51 are spaced in axial alinement for rotation inopposite directions.

A common shaft 52 sus ceptible of being driven by either of the mo Parallel with'and in spaced relation above the shaft 56 is positioned a second shaft 58 journaled for free rotation in suitable bearings carried by the posts 54 and 55, said shaft 58 carrying a gear 59 in fixed relation therewith between saidposts and in meshingrela-l tion with a pinion 6O fixed to and rotatable with the worm wheel 57. l/Vith the arrangement above described, it is apparent that operation of either of the motors or 51' acs through the shaft 52, worm 53, worm wheel 57, pinion 60and gear 59 to rotate the shaft 58 inone' direction, while operation'of the other motor acts to rotate said shaft in the opposite direction. The shaft 56 is extended axially beyond the post 54 to support a bracket 61 freely rotatable .on 'saidjshaft and projecting laterally on each side thereof,- from the upper side of which bracket 'rise'.

arcuate fingers 63 in fixed relation with said bracket and with theirconcave sidesin opno I position and in embracing, eccentric relation ,with theextended endof theshaft 58. Di-

rectly beneaththe bracket 61; is positioned a double-acting switch comprising a base portion 6a secured to and extending longitudinallyof-the basej lfi) and provided with a pair of spaced'contacts adjacent each of its ends, and a movable upper portion 65 hinged at its transverse .center in spaced relation above I the portion Geand provided with a pair of spaced contacts at each end adapted to engage at times the contacts of the adjacent ends of the portion 64, the hinge axis of said-switch assemblybeing parallel with the shaft '58; Spring fingers 66 rise from and .9 extend in opposite directions longitudinally of the switch portion 64, and adjustablepushrods ,67 connect between each of said spring fingers andrthe corresponding lateral extension of the bracket "61,-so that oscillation of saidbracket on thesha'ft 56 acts to oscillate I the switch portion 65 to one or the other of its closed circuit positions, travel of said bracket beyond that required to close the switch being permitted by the yieldingcharacter of the spring fingers 66. An arm 68 is fixed to and extends radially from the end of the shaft 58'adjacent the arcuate fingers 63 and supports on its free end a roller 69 arranged for peripheral engagement with the concave surfaces of said fingers when the said "shaft 58 is rotated, the arm 68 being of such 7 length as toposition the roller 69 in engagement with the lowermost portion of the yoke formed by the fingers 63 when the shaft 58 is in its normal'or median position, which arrangement operates, when the shaft 58 is rotated, to swing vthe bracket and finger assembly, 61'63, about its mounting on the shaft 56-for oscillation of the switch portion 65 to one orthe other of its-closed circuit 7 positions. Spaced equally from and, on opprises a base portion fixed to thebase49 and pqsite sides of thesviitch64 -65, identical switch assemblies 70 and 71 are positioned on the base 49 adjacent the motors 50 and-51..

Each of the switch assemblies 70 and 71 comprovided with a pair ofspaced contacts and an upper portion hinged at one end to the base portion for actuation through avertical arcirelative thereto and provided with a pair of spaced contacts adapted to engage the contactsof its base portion at times, said switch assemblies being mounted on the base 49. with their hinged ends adjacent the switch assembly 64rf65. and rise perpendicularly from the hinged Fin ers 72 are fixed'to upper portions of the switch assemblies 70 and 71 and retractile coil springs 7 3 engage between upper portions of said fingers and the base'49 to yieldingly'hold said switch assemblies in normal'closed circuit position.

Means operable through rotation of the shaft 58 are provided whereby either of the switch assemblies 70 or 71 may be automatically actuated, at times, against the ten sionof its springs 73 to open I, circuit position, .said means comprisinga hub 7 .2 loosely'mounted on the shaft 58 between thea-rm'68 and the post 54,'from"which hub extend diametrically-opposed, radial arms 75 and 76. The hub 7 4 is normally so positioned as to dispose the arm 7 5 in verticalposition above'the'shaft 5-8 and the arm' 76 in vertically-depending relationb'elow saidshaft, saidlatter arm be ing formed with an elongated, horizontally:

disposed loop on its lower end in embracing relation with the shaft 56 and'a downward extension? 6- depending from said loop below said shaft-56 in 'alinement with said arm '76..

so u

chains 77, engage between and connect at:

tachin oints of the extended fin ers 72 and arm extension 76,'s0 that, when the arm extension 7 6',-1s 1n itsnormal, vertlcal posltion' both switch assemblies 70 and 71 are held in circuit closing relation by their springs 7 3, arcuate travel of said arm exten-,

sion in one direction exerting a pull on one of the connecting chains 77 J which acts through'its finger 7 2 to overcome the tension of the corresponding springs 73"" and open one of the switch'assembl-ies, opposite'travel' of said arm extensionactingin the same manner toopen the other of the switch assemblies.

To operate the abovedescribed switch actu'at ing means, an arm 78 is fixed to and extends substantially radially-of the shaft 58 adjacent ando at approximately right angles with the arm 68, which arm 78 is formed with an end lug 7 8 lying in the plane of rotation'of the arms. 7 5" and 76 andjsubstantiallyhalf way therebetween,so that, as said shaft 58, and arm 78 are rotated,'-said lug 78 travels into engagement with, one or the other of the arms 7 5 and '76 and rotates the hub 7Lslightly on said shaft 58, whichhub rotation actsrto swing the arm extension- 76 and exert the pull on one of the chains 77 necessary to unseat one of the switch assemblies 70 or 71.

Adjusting -;screws 79 I are ,operatively positioned through the arms? 5 and 7 Stangential to the orbit of rotation of the lug 7 8 and in position. to be engaged by said lug, so that adjustment of the range of travel of said lug prior to its operationof theswitch ac-' tuating means may readily be had through aCl]lISt111eI1t of the pro ect1on ofv said screws relative to the faces of their respecti've arms. A further. means of varying the inoperative;

travel of the lug 7 8 which maybe employed Y at will and without disturbing any of'the ad justments of the assembly, is provided, said latter means comprising a relatively thin disc 80 mounted in loosely embracing, concentric and perpendicular relation with the shaft 58 between the radial arms 68 and 78 and supported by means of a hinge connection 81 with the outer end of a radial arm 82 extending in fixed relation from said shaft 58 at substantially right angles with the arm 68, the free side of said disc 80 being thus mounted for limited motion toward and away from the lug 7 8. Identical lugs 83 are spaced apart on and extend in fixed relation perpendicularly from the face of the disc 80 adjacent the arm 78, said lugs being spaced apart a distance equal to the width of the lug 7 8 and so positioned on said disc as to embrace said lug 7 8', the length of the lugs 83 being such as to permit them to pass freely by the arms and 76 when the disc is adjacent the arm 68 and the shaft 58 is rotated and such as to bring them into intersecting relation with the vertical plane of said arms 7 5 and 7 6 when said-disc is moved adjacent the arm 78,.in which latter position the lugs 83 embrace and lie on opposite sides of the lug 7 8 and may engage and operate the arms 75 and 76 in the same manner as would the lug 7 8', the interposing of said lugs 83 thus serving to operate said arms 7 5 and 76 with less rotation of the shaft 58 than is required for the lug 78 alone. Any suitable means for manually controlling the position of the disc may be employed, one such means being illustrated as comprising a horizontally-disposed rock-shaft 84 from which a fixed finger 85 rises to embrace at its upper end the movable margin of said disc, a fixed lever 86 depending from said rock-shaft in operative engagement with a latchable slide bar 87, arranged for manual adjustment, providing means for actuating said rock-shaft to adjust said disc to either of its two limits, as may be desired. The shaft 58 is the control surface operating element of the entire assembly and is arranged to be so connected to the control surfaces of the craft to be stabilized as will best give effect in a specific installation, the arrangement shown in Fig ures 1, 2, 3, 8, 9 and 10 being particularly adapted for use with aircraft. In the figures last above noted the shaft 58 is illustrated as extendedaxially beyond the post 55 to provide support for a suitable drum or grooved pulley 88 mounted for free rotation thereon, flexible cables 89 being secured to said drum and leading in opposite directions therefrom through suitable guide pulleys 90 to operative connection with the normal control cables 91 of the craft. The connection between the cables 89 and 91 may be made in any suitable manner, but for best results it is desirable that a resilient element be provided in each cable 89 between the drum 88 and the point of connection with the cable 91, one satisfactory form of such an element being illustrated at 92 in Figures 2 and 3.

In the showing of Figure 1 a conventionalized airplane is illustrated with a main'wing 93 provided'with hinged wingflap s or ailerons 94 to which the control cables 91 are led froma control'stick 95 in a common manner 3 to provide means for manually controlling the lateral position of said main swing, the arrangement shown being but typical of manysuch varyingonly in detail.- When the drum 88is connected into the control system as shown in Figures 1 and 2, it becomes a part of said system and so long as the'drum is free to rotate on its shaft it interferes in no way wlth the normal manlpulatlon of the controls, rotating in one direction or the other as the stick 95 is swung to actuate the surfaces 9.4, it being obvious that rotation of said drumunder the influence ofithe apparatus previously described would have the same effect on the surfaces 94Las would be had through corresponding movement of the stick 95. To make the drum 88 eflectiveiin the operation of the controls 91, means are pro-' vided for locking said drum to the shaft 58 for rotation therewith, when desired, said means'being illustrated as a spring-pressed pin or plunger 96 spaced fromand in parallel relation with the. shaft 58 and mounted for axial reciprocation in suitable guides 97 fixed to said shaft, said pin .96 being arranged to engage at one end within a hole.

formed in the drum :88 and thus lock said drum to the shaft 58, said holebeing so positioned as to synchronize the neutral posi tion of the cables 89 attached to said drum with the neutral position of said shaft. The pin 96 is normally spring-pressed into looking engagement with the drum 88, but may be withdrawn from such engagement when it 1s desired to release thecraft controls from the automatic action of the invention, a. manually-operable throw 98 hinged toone of the guides 97 and operatively connected with the pin 96 being illustrated as one suitable means whereby saidpin may be withdrawn and retained in 7 its. disengaged relation. I s

The'elements of the-apparatus hereabove described are electrically interconnected for effective automatic operation as shown in 99 designates a source of electrical energy,

such as a storage battery, which is mounted the switches 36 an'd 70 areclosed,' a closedcire;

cuit including. the source of energy 99 and the .motor 50 is established; In-like manner acircuit 102 leads from the side of the switch 115 i Figure 14:. In said latter figure, the numeral 37 opposite the circuit 100 through i the s'witch'7l to operative connection with the motor 51, so that, when said switches 37 and 71 are closed, the motor 51 is'operatively in:

c'luded'in the circuit from said source of enf V 'ei'gy. That ,portion or the circuit 100 con "nectin'g'with theswitch 38 is continued beyondsaid switch as the circuit 103 which leads to the switch element where it is branched for operative connection with the contactscarried at each end of said element, lead's 104'oper'atively connecting the contacts at one end of the switch base 6t'with the cirits,

circuit-@102 between the switches37 and 71.

c nit' '101 between the switches 36 and' and similar leads 105 connecting thecontacts at the other end oftheswitchb'ase 6 1 with the I In :the' practical operation of the apparastalled 13S] above described, the 'assembly'15 assumes and retains its balanced position so' long asthe-mainwmg 93 of the craft is substantiallyhoriz ontal, the switches 38,"?0'and "sition of the drum 88 vonits shaft 58 and.

' 71 are clo'sed,the-switches 86, 37 and 64-65 a 7. op'en-and'the wing flaps 94" in neutral relation with the main wing'by'virtue of the poproperadjustment and interconnection of the cables "89 and 91, the motors 50 and 51 beinghence inoperative so long as the lateral balanceof the craft is'inaintaine'd. When I the, main wing 93, is moved out ofits hori- "fzontal "position an appreciable amount, the I jflow of liquid in the cells 16tilts the assembly 15't'oward the low end of said wing, which action closes the switch 86 or 37 adjacent said'low end' and simultaneously opens the switch 38, thus'closing a circuit from the 6 source of energy 99 to one, or the other'of the motors '50, 51,'actuating said motor to rotatethe shaft 58' and drum '88 and'consequent- 1y set'thfe wing flap-s 94' as maybe required to" return the main wing to its horizontal position, the op'er'ation of said motor being continued until its switch 70 or 71 is automatically opened through'contact of the lug I 7.8 with one of the arms 7 5 or 7 6; during 7 which time the roller69 has acted through the fingers 63 toclose that end-ofthe switch 64+65' controlling the, inoperative motor.

.As the operation o t'the motor is arrested,the

wing flaps94 are set to return the main wing to normalvpositionyoneof theswitches 36', V

37 isopen' and the other closed, the "switch a 38- is open, one of the switches 70, 71 open I and the otherclose'd and the end of the switch 64. 65" controlling the previously inoperativemotori closed, no circuit being completed rne nts remainuntil the main wing approaches its normal position. As the main wing 'ap proachesthehorizontal and the liquid in the 7 ,cells 16 flows back towardsthemidportion of th'ega'ssembly 15, the balancing devices, of said '4 assembly return the-latter to its balanced "wing 931i's displaced fromitsi normal horitus constructed, arranged, connected and" in-' fing'with the circuit'lOQ between'the switches 3? and 71 and hence re'gisteringto'indicate of the main wing. v i I c It is of course obviousthat use of the 38, thereby completing a circuit from the source of energy to the previously inoperative position, which action also closes the switch motor, actuating said motor and thereby leavingthe elements of the'appa'ratus in the relation shown in the drawings and ready for repetition of the cycle whenever' the main zontal position. 'As a 'visualcheck on the relative position of themain'wingand onthe operation of the apparatus, electrical indicators, indicated conventionally as incandesj- 7 cent bulbs 106, may be -'conven1ently arranged, as on the instrument'panelofthe craft, and operativelyconnected as'shown in Figure 14, the righthand indicator'connect a low right wing when the sweets? is closed, the leitha'nd' indicator connecting with the circuit 101 between the switches '36 and'il') for registration to indicate a low left v wing when the sw1tch=36 is closed,-{ and thecenter indicator connecting with the circuit 103 between the switches 38 and 64 65 for registration whensaidswitch 38 is'closed, thus indicating approximate paratus is not limited to control of the lat eral stability of the craft,'but maybe extended to control the. logitudinal stability as well, in which latter casetl e base 2% i s'posi- V tioned longitudinally of and in the normal horizontal plane of the craft and the-drum '88 is operatively. connected with the convator of 'the craft, ,,.T hus two installations of 'the' apparatus ona s1ngle craft 'provide normal position v tro'ls operating theho'rizontalirudderorelecomplete automatic control whereby tlie craft may be maintained in lateral andlcn-f v gitudinal-balance in a horizontal plane, either or both such installationsbeing readily dis;

connectedto'permit manual operation of the controls, whendesired.

The reasons for dividing theassembly 15 7 into 'a'plurality of relatively small 'longi 't'udinal-cells are several and of najor'p'rac meal-importance. ii Vere the assembly 15 a single cell orboxhaving thesaine capacity as the assembled cells 16 and charged with the same ainount ofrliquid, the-Pcentecof' gravity of the assembly would bemuch: lower fthan'is the case, 111 the arrangement shown and the liqnid contents ofthe assemblywould 1 surge and .splashtoa marked degree, caus-' ing the assemblytofoscillateanddestroying much of its operativeiefficiency. Thesmall amount of liquid contained in each of'the cells shown is less subject to inertia effects and comes rapidly to rest when the assembly assumes one or another of its positions, thus making for rapid and postive action of the switches controlled by the assembly. Again, particularly in aircraft, there may be inclination of the assembly axis out ofthe horizontal at a time when it is desired to have the assembly function, in which event it is highly important that the liquid be confined in relatively small cells to prevent displacement of the center of gravity to an extent destructive of operative effect; in a single cell or box, the liquid would naturally pile against one or the other of the side walls when the assembly axis was inclined, but with the cell construction shown the liquid is retained in the various compartments where is continues to function under the influence of gravity, as described, until the assembly axis approaches'the vertical. The cells may be employed in various arrangements and in such number as may be indicated to give desired results in a specific installation, but

a single, large cell is so subject to inertia efi'ects acting through its liquid as to be highly unsatisfactory.

In Figures 11, 12 and '13 is illustrated a conventional adaptation of the invention to watercraft for the purpose of enhacing lateral stability and minimizing rolling thereof. In the figures last abovenoted, a watercraft is indicated generally by the numeral 107, on which craft the apparatus comprising the invention is suitably positioned, the box or housing 108 representing an installationof the complete apparatus. On opposite sides of and well below the normal waterline of the craft, suitable keel-rudders 109, each extended laterally and longitudinally in the horizontal plane and contoured to oifer minimum resistance to its passage through the water in the direction of the craft travel, are fixed to the ends of alined shafts 110 mounted for rotation transversely of the craft. On the inner, adjacentends of the shafts 110 are fixed identical, segmental bevel gears 111 which'mesh with opposite sides of a bevel pinion 112 fixed on one end of a longitudinally-disposed, rotatable shaft 113, a gear 114 on the other end of the shaft 113 meshing with a pinion 115 carried by the shaft 58 of the apparatus, so that rotation of said shaft 58 acts to rotate the shafts 110 simultaneously and in opposite directions, the arrangement of the apparatus being such that rotation of said shaft 58 acts to incline the keel-rudder 109'on the low side of the craft to elevate that side of the craft as it moves through the water and to incline the keel-rudder on the high side of the craft to lower that side, the operation of the elements of the apparatus being the same with reference to the lateral inclination of the craft as havebeen previously described for aircraft;

t is obvious that many changes in the specific form, construction and arrangement of the elements of the invention may be had 3 without departing from the spirit thereof, and that specific installations of the apparatus may require infinite variation of the specific mechanical means, and connections Wherethrough' the automatic action of the apparatus is made effective, hence I wishitobe understood as being limited solely :by the scope of the appendedv claims rather than.

any details of-the illustrative foregoing description. I claim as my inventionshowing and 1. In combination with a fluid-traversing craft having relatively-movable, fluid-engage ing elements whereby the horizontal attitude V of said craft may be controlled, means automatically operable to stabilize said craft relative to one of its horizontal axes, said means comprising a-tiltable unit mou'ntedon said craft for limited oscillation inia plane-perpendicular to the axis: about which stabilizing effect is desired, yielding means-operableto normally positlon sa d "unit intermediate the limits of its range of travel, normally open switches adjacentthe-ends:of said unit and arranged to be individuallyclosed by downward motion of the corresponding end of said unit, independent electrical circuits controlled by said switches, an electric motor in each of said circuits, a shaft arranged to be driven in one direction'by one of said motors and in the opposite direction by the other of said motors, and operative connections between said shaft and the relatively-movable craft elements. l I

2. In combination. with a fluid-traversing craft having relatively-movable, fluid-engaging elements whereby the horizontal attitude I of said craft may be controlled, means automatically operable to stabilize said craft relative to one'of its horizontal axes,;said means comprising a tiltable unit mounted onsaid craft for oscillation in a plane perpendicular to the axis about which stabilizing effect is desired, yielding means operable to normally position said unit in vertically balanced relation above its axis, normally open switches ad]acent each'end of said unit and arranged to be individually closed by downward motion ofthe correspondingend of said unit, independent electrical circuits controlled by said switches, an electric motor in each of said said motors.

3.- Incombination with fiuidetraversing effect is to be had, yieldable means normally positioning said control unit intermediate 7 the limits of its range of travel, an operating unit including a pair of motors arranged for opposite rotation, ashaft in driven relation with'o said motors,-foperat ve connections between said shaft and therelatively-movablc 1 craft elements and electrical means and connectionswhereby tilting of said control unit may act to selectively energize said motors.

In combination with afiuid-traversing of'said'craft may be controlled, means automatically operableto's'tabilize,said craft rela-f tive to one of its horizontal, axes, said means comprising P2111 operating 7 unit 7 including a pair 'o f'motors arranged from. opposite romama shaft in driven relation with said. motors, operativeconnections between said shaft and the relatively-movable craft 7 eleneiitspa gravity-operable, tiltable unit ar- -range,d' with" its axis of oscillation parallel with that c'raftaxis about which stabilizationis; desired, electrical 'means and connections wherethrough oscillation of said tiltable unit may act' to selectively energize said motors, automatic means operable through rotation :of said shaft to arrest the oper-' ation of either'of said motors and further,

operable to complete a circuit to the previously inoperative motor as said tiltable unit approaches its normal balanced position.

5. In a stabilizing device, a base positioned normally ina horizontal plane, an axis car- 'riedby said basein parallel relation with the axisof stabilization, a gravity-tiltable assembly-mounted :above and for limited oscillati'on relative'tosaid axis, said assembly comprising a plurality of identical, elongated cells eachforminga dihedral'angle in the planeof its oscillation, said cells-being arranged with their apices in a common plane includingltheaxis of oscillation and diverge ing upwardly and outwardly from said plane and in closelynested, compact interrelation, liquid partially filling each ofqsaid cells, yielding means engaging between saidfcell assembly {and said base to normally position I the former in its balanced, median relation,

electricalcircuits including switches "in 0perativezrelation with said cellassembly, and

a power; assembly s'ervedby saidcircuits.

6, In a stabilizing device,fa base positioned normally in a horizontal plane, an axis car= riedby saidbase in parallel relation with the axis of stabilization, a gravity-tiltable as craft having relatively-movable, fluid-engag- 7 'ing elements whereby the horizontal attitude sembly mounted above and for limited :oscillation relative to said axis, said "assembly comprising a plurality of identical cells in compact, closely nested interrelatiom; said cellsdiverging upwardly and outwardly from ar vertical plane containing said axis and being each partiallyzlilled with liquid, means and connections carried bysaid base where- 1 by said cell assembly may be yieldingly held in its balanced, median position when said base is horizontal, a normally open switch adjacent and in operative connection with each end of said cell assem ly closable through, tilting action ofrsaid assembly, a normally closed switch adjacent,

the midportion of said assembly-and arranged. to be opened through ,tilting of said assembly, electrical circuits controlled by saidswitches and said circuits. r

7, In a-stabilizingdevice, a drivenshaft operable to r position stabilizingfelements, a pair of electric motors arranged for opposite rotation and in driving relation with said shaft, normally open circuits serving said motors, normally-balm ced, gravitystiltable control unit automatically operable to, close one or the other of said circuitsiwhen unbalanced, means/operable by rotation "ofsaid shaft to automatic ally open the circuit to an,

operative' notoi" at -a predetermined point in therotation of saidshaft, said last means bea power assembly served by H a r r and selectively ing further operableito close a supplemental circuit to the previously inoperative motor and a switch in operative relation with said control unit and operable as said unit'.appreaches its. balanced position to complete said supplemental circuit and energize said previously inoperativefniotor whereby said shaft isreturned to normal position. 2 8. In a stabilizing device, a driven shaft operableto position stabilizing elements, a

pair of electric motors arranged foroppo-I site rotation and in driving relation with said. shaft, speed-reducing gearing between said. motors and shaft, normally open circuits servrng'said motors, anormally-balanced, gravity-tiltable control unit automatically operable to close one or the other of said circuits when unbalanced,-means operable by rotation of said shaft to'automatically open the circuitto an operative motorat a predetermined point in the rotationjof said shaft, 'said means including switcl es in each. motorcircu t, an armmounted for free ro tatioii on said shaft and extending-radially on each side thereof, spring means normally holding said switches in closed position, flex} ible connect ons between the depend ng portion of said arm and said switch s whereby the latter may be opened aga nst the'pressure V of their springsyandzan arnrfixed to saidl shaft for rotation therewith and formed with a lug adapted to engage one or the other of; the firsta-rm extensions and swing thelatter about said shaft to switch-opening position; together with means operable by rotation of said shaftv to establish a supplemental circuit to the previously inoperative motor for return of said shaft to its normal position as said control unit approaches its normal balanced relation.

Signed at Denver, in the county of Denver and State of Colorado, this third day of December, 1931. a

I WILLIAM CHATER. 

